Object detecting device having three-axis adjustment capability

ABSTRACT

There is provided an object detecting device having a capability of easily adjusting a detection area in three-axis directions. This object detecting device (D) having the three-axis adjustment capability includes an antenna (AT) for transmitting and receiving a sensing wave and also includes a first holder ( 2 ) supported by a support platform ( 1 ) for rotation about a first axis (R 1 ), a second holder ( 3 ) supported by the first holder ( 2 ) for rotation about a second axis (R 2 ) lying perpendicular to the first axis (R 1 ), and an antenna module ( 4 ) holding the antenna (AT) and supported by the second holder (R 2 ) for rotation about a third axis (R 3 ) lying perpendicular to the second axis (R 2 ).

FIELD OF THE INVENTION

The present invention generally relates to an object detecting devicefor an automatic door or for security monitoring purpose and utilizing asensing wave such as a microwave and, more particularly, to the objectdetecting device having a capability of easily and quickly adjusting adetection area in three-axis directions.

BACKGROUND ART

The general object detecting device for an automatic door or forsecurity monitoring purpose radiates a sensing wave such as a microwavetowards a detection area and then receives the sensing wave reflectedfrom a human body intruding the detection area to detect the presence ofthe human body in terms of a change in the frequency of the sensing waveas a result of the Doppler effect. The object detecting device of thistype known in the art makes use of a patch antenna made of a metallicfoil and includes a dielectric lens that is arranged rotatably in frontof the antenna and becomes either a convex lens or a concave lens whenrotated 90°. See, for example, the Japanese Laid-open Patent PublicationNo. 7-110375. In this known object detecting device, the detection area(either a wide area or a narrow area) can be adjusted by rotating thedielectric lens through 90° and the manipulation for the adjustment caneasily be performed.

DISCLOSURE OF THE INVENTION

However, even with the above object detecting device having therotatable dielectric lens, the extent to which the detection area isadjusted or changed is limited and no satisfactory adjustment can beaccomplished since only one lens is rotated.

The present invention has been developed in view of the foregoingproblems and is intended to provide an object detecting device having athree-axis adjustment capability, in which three-axis adjustmentsincluding adjustments of the detection area in a leftward and rightwarddirection (i.e., in a first horizontal direction) and also in a forwardand rearward direction (i.e., in a second horizontal directionperpendicular to the first horizontal direction) and selection of one ofa wide area and a narrow area can be accomplished easily and quickly.

To this end, the present invention in accordance with one aspect thereofprovides an object detecting device having a three-axis adjustmentcapability for transmitting and receiving a sensing wave through anantenna, which device includes a support platform, a first holdersupported by the support platform for rotation about a first axis, asecond holder supported by the first holder for rotation about a secondaxis lying perpendicular to the first axis, and an antenna module havingthe antenna and supported by the second holder for rotation about athird axis lying perpendicular to the second axis.

According to the foregoing object detecting device having the three-axisadjustment capability, turn of the first holder about the first axis iseffective to accomplish the adjustment of the detection area in aleftward and rightward direction. Also, turn of the second holder aboutthe second axis is effective to accomplish the adjustment of thedetection area in a forward and rearward direction. Yet, turn of theantenna module about the third axis is effective to change theorientation of the antenna to change the shape of the detection area toone of wide and narrow areas. Thus, since the three-axis adjustment ofthe detection area can be performed easily, the installation of theobject detecting device can easily and quickly be performed on site.Also, since the change of the shape of the detection area can beaccomplished merely by changing the orientation of the only antenna,there is no need to use two dedicated antennas and, therefore, thenumber of component parts used can advantageously be decreased tothereby reduce the cost of manufacture of the object detecting device.

In a preferred embodiment of the present invention, each of the firstand second holders is so shaped as to represent a semisphericalconfiguration. By so doing, not only can a structure necessary torotatably support the first holder and the second holder relative toeach other be simplified, but the operationality in rotating the firstholder relative to the support platform and also in rotating the secondholder relative to the first holder can also be increased.

In another preferred embodiment of the present invention, the supportplatform may include a base member having a substrate and secured to anexternal support member, and an inner cover for covering the basemember. The substrate has electronic component parts mounted thereon. Inthis case, the first holder has a lower outer peripheral portionsandwiched between the base member and the inner cover. According tothis feature, not only can the substrate having the electronic componentparts and mounted on the base member be protected by the inner cover andthe first holder, but the first holder can be also supported on thesupport platform with no need to use any mounting member. Therefore, amechanism for rotatably supporting the first holder can advantageouslybe simplified.

In a further preferred embodiment of the present invention, the objectdetecting device may also include a first intermittent engagement forintermittently engaging the first holder with the support platform toprovide a feeling of a click as the first holder rotates relative to thesupport platform. According to this feature, the operator or attendantworker can turn the first holder while perceiving a feeling of a clickand, therefore, the adjustment of the detection area in the leftward andrightward direction can be facilitated.

In a yet further preferred embodiment of the present invention, theobject detecting device may further include a second intermittentengagement for intermittently engaging the second holder with the firstholder to provide a feeling of a click as the second holder rotatesrelative to the first holder. According to this feature, in a mannersimilar to the first intermittent engagement, the second holder can beturned while the operator or attendant worker perceives the feeling ofclick and, therefore, the adjustment of the detection area in theforward and rearward direction can be facilitated.

In a yet further preferred embodiment of the present invention, theantenna module may be mounted on a top mount of the second holdersandwiching the top mount between a holding member for holding theantenna and a back plate that form respective parts of the antennamodule. According to this feature, the antenna module can be mounted onthe second holder with a simplified structure without requiring anyextra mounting member.

As discussed above, in the object detecting device having the three-axisadjustment capability according to the present invention, the adjustmentof the detection area in the three-axis directions can be easily andquickly accomplished at the site of installation of the object detectingdevice. Also, dedicated antennas for setting the wide area and thenarrow area, respectively, are not required in the present invention andthe turn of the only antenna is sufficient to select one of the wide andnarrow areas. Therefore, the number of component parts employed canadvantageously be reduced and, also, the cost of manufacture of theobject detecting device of the present invention can be suppressed to alow value.

BRIEF DESCRIPTION OF THE DRAWINGS

In any event, the present invention will become more clearly understoodfrom the following description of preferred embodiments thereof, whentaken in conjunction with the accompanying drawings. However, theembodiments and the drawings are given only for the purpose ofillustration and explanation, and are not to be taken as limiting thescope of the present invention in any way whatsoever, which scope is tobe determined by the appended claims. In the accompanying drawings, likereference numerals are used to denote like parts throughout the severalviews, and:

FIG. 1 is a cross-sectional view taken along the line I-I in FIG. 2,showing an object detecting device having a three-axis adjustingcapability according to a first preferred embodiment of the presentinvention;

FIG. 2 is a front elevational view of the object detecting device, asseen through a dome-shaped outer cover;

FIG. 3 is a front elevational view of a base of the object detectingdevice;

FIG. 4 is a front elevational view of an inner cover of the objectdetecting device;

FIG. 5A is a perspective view showing a first holder employed in theobject detecting device;

FIG. 5B is a bottom plan view of the first holder;

FIG. 5C is a perspective view, on an enlarged scale, of an engagementpiece mounted on the first holder;

FIG. 6 is a perspective view showing a second holder employed in theobject detecting device;

FIG. 7 is a front elevational view showing the manner in which anantenna module employed in the object detecting device is turned;

FIG. 8 is a diagram showing a movement of a detection area in a leftwardand rightward (horizontal) direction;

FIG. 9 is a schematic diagram showing a movement of the detection areain a forward and rearward direction;

FIGS. 10A to 10C are diagrams showing the shape of an wide area whenviewed from different angles;

FIGS. 11A to 11C are schematic diagrams showing the shape of a narrowarea when viewed from different angles and

FIG. 12 is a circuit block diagram showing an object detecting systememployed in the object detecting device.

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, preferred embodiments of the present invention will bedescribed with reference to the accompanying drawings.

FIG. 1 illustrates, in a cross-sectional representation taken along theline I-I in FIG. 2, an object detecting device D having a three-axisadjusting capability according to one preferred embodiment of thepresent invention and FIG. 2 illustrates the object detecting device Din a front elevational representation.

Referring to FIG. 1, the object detecting device D has a supportplatform 1 including a base member 11 (Also see FIG. 3.) and an innercover 12 (Also see FIG. 4.). The base member 11 has a substrate 13mounted thereon and is secured to an external support member such as abuilding wall, a building ceiling or a transom over an automatic door.The inner cover 12 covers the base member 11. The substrate 13 haselectronic component parts E1 mounted thereon and forming respectiveparts of an object detecting circuit.

A first holder 2 of a semispherical configuration (Also see FIG. 5A) hasa lower outer peripheral edge 2 a movably sandwiched between the basemember 11 and the inner cover 12 so that the first semispherical holder2 can be turned about a first axis R1 lying perpendicular to a bottomsurface 11 a of the base member 11 that serves as a mounting surfacethrough which the object detecting device D can be secured to theexternal support member referred to above. This first axis R1 may notlie perpendicular to the bottom surface 11 a, but in any event extendsso as to intersect the bottom surface 11 a. The base member 11 and theinner cover 12 are connected together by means of screws 6 arranged at aplurality of, for example, five locations as shown in FIG. 2.

A second holder 3 (Also see FIG. 6) of a semispherical configuration issupported within the first semispherical holder 2 for rotation about asecond axis R2 lying perpendicular to the first axis R1. As a means forsupporting the second semispherical holder 3 within the firstsemispherical holder 2, the second semispherical holder 3 has a pair ofsupport studs 31 and 31 formed therein in alignment with the second axisR2 as shown in FIG. 6, which studs 31 and 31 are rotatably engaged incorresponding stud holes 22 and 22 formed in respective portions of thefirst semispherical holder 2 that are aligned with the second axis R2 asshown in FIG. 5A.

As shown in FIG. 1, an antenna module 4 for transmitting and receivingsensing waves, for example, microwaves is mounted on a top mount 32 ofthe second semispherical holder 3 for rotation about a third axis R3lying perpendicular to the second axis R2. This antenna module 4includes a holding member 41 for holding an antenna AT and a back plate42. The antenna module 4 is rotatably mounted on the top mount 32 of thesecond holder 3. Specifically, the holding member 41 and the back plate42 are connected by two screws 44 with the top mount 32 sandwichedbetween the holding member 41 and the back plate 42 to thereby allow arotational movement of the antenna module 4 relative to the secondholder 3. The back plate 42 has a rear surface, on which a substrate 43having electronic component parts E2 of a transceiver circuit mountedthereon is mounted. The antenna AT is, as shown in FIG. 2, in the formof a two-dimensional wire, for example, a zigzag-shaped wire. Theantenna module 4 is movable in a forward and rearward direction betweena position P1, shown by the solid line in FIG. 1, and a position P2,shown by the phantom line, within an opening 21 of the firstsemispherical holder 2 by turning the second holder 3 about the secondaxis R2.

A substantially dome-shaped outer cover 5 made of a synthetic resin iscapped onto the support platform 1 to enclose and protect the firstsemispherical holder 2, the second semispherical holder 3 and theantenna module 4. An indicator element P, for example, a light emittingdiode (LED) having one end connected with the substrate 13 is providedbetween the base member 11 and the inner cover 12 and is viewable fromoutside through the outer cover 5 so that whether or not the objectdetecting device D is activated can be ascertained from the outside.

A first intermittent engagement 9 is provided between the supportplatform 1 and the first semispherical holder 2 for intermittentengagement between the support platform 1 and the first semisphericalholder 2, as the first holder 2 is turned about the first axis R1, sothat during the first semispherical holder 2 being so turned, theoperator or attendant worker can perceive a feeling of a click, that is,can feel intermittent engagement on worker's fingers. Similarly, a pairof second intermittent engagements 10 (FIG. 2) is provided between thefirst semispherical holder 2 and the second semispherical holder 3 forintermittent engagement between the first holder 2 and the second holder3, as the second holder 3 is turned, so that during the secondsemispherical holder 3 being so turned, the operator or attendant workercan feel a similar clocking sound.

The first intermittent engagement 9 includes an engagement piece 91 inthe form of a metallic plate fixedly mounted on the base 11 of thesupport platform 1 as shown in FIG. 3 and a series of engagementserrations 91 formed in an end face of the first semispherical holder 2as shown in FIGS. 5A and 5B. This first intermittent engagement 9 is sodesigned that during the turn of the first semispherical holder 2 theengagement piece 91 can be intermittently engaged with the engagementserrations 91 to provide the feeling of click to the operator orattendant worker. The turn of the first semispherical holder 2 can becarried out while the operator or attendant worker looks at calibrations14 formed in an edge portion of the inner cover 12 as shown in FIG. 4and, accordingly, a highly accurate adjustment can be accomplished.

Similarly, each of the second intermittent engagements 10 shown in FIG.2 includes a respective engagement piece 101 in the form of a metallicplate fixedly mounted on an inner surface of the first semisphericalholder 2 as shown in FIGS. 5A to 5C, and a series of engagementserrations 102 formed in an outer surface of the second semisphericalholder 3 as shown in FIG. 6. This second intermittent engagement 10 isso designed that during the turn of the second semispherical holder 3the engagement piece 101 can be intermittently engaged with theengagement serrations 102 to provide the feeling of click to theoperator or attendant worker. The turn of the second semisphericalholder 3 can also be carried out while the operator or attendant workerlooks at calibrations 23 formed in an edge portion of the opening 21 ofthe first semispherical holder 2 as shown in FIG. 5A and, accordingly, ahighly accurate adjustment of the second holder 3 can be accomplished asis the case with the first semispherical holder 2.

The object detecting device D so constructed as hereinabove described ismounted on, for example, a transom 82 over an automatic slide door 81,as shown in FIG. 10, through mounting holes 7 (FIG. 2) defined in thesupport platform 1. Setting of the detection area that can be covered bythe object detecting device D is carried out in the following manner. Inthe first place, setting of the detection area in a leftward andrightward direction is carried out by turning the first semisphericalholder 2 relative to the support platform 1 (FIG. 1) over apredetermined angular distance about the first axis R1 in a directionshown by the arrow A. At this time, when viewed from top, the detectionarea moves leftwards or rightwards relative to the door 81 or in a firsthorizontal direction substantially parallel to the door 81, as shown byS1 or S2 in FIG. 8, respectively. Setting of the detection area in aforward and rearward direction (in a second horizontal directionperpendicular to the first mentioned horizontal direction and also tothe door 81) is carried out by turning (or angularly moving forwards orrearwards) the second semispherical holder 3 relative to the firstsemispherical holder 2 (FIG. 1) over a predetermined angular distanceabout the second axis R2 in a direction shown by the arrow B. At thistime, when viewed from top, the detection area moves forwards orrearwards relative to the door 81 in the second horizontal direction asshown by S3 or S4, respectively, in FIG. 9.

Selection of one of detection area shapes including a wide area and anarrow area is carried out by turning the antenna module 4 relative tothe second semispherical holder 3 (FIG. 1) over a predetermined angulardistance about the third axis R3 in a direction shown by the arrow C inFIG. 7 to change the orientation of the antenna AT. Specifically, whenthe antenna module 4 is turned to orient the antenna AT in a directionshown by the solid line in FIG. 7, the wide area W can be set, whichcovers an area of large width in front of the site of installation ofthe object detecting device D, as shown in FIGS. 10A and 10B. Thedetection area represented by this wide area W represents a transverselyelongated, substantially oblong shape (as shown in FIG. 10B) when viewedfrom top, which oblong shape has a width W1 (FIG. 10A) as measured on afloor 83 when viewed from front and, also, has a relatively small depthL1 as measured on the floor 83 when viewed from laterally. The detectionarea represented by this wide area W is conveniently employed for asensor suitably used in association with an automatic double door 81.

When the antenna module 4 is turned to orient the antenna AT in adirection shown by the broken line in FIG. 7, the narrow area N can beset, which has an area of small width in front of the site ofinstallation of the object detecting device D as shown in FIGS. 11A to11C. Specifically, the detection area represented by this narrow area Nrepresents a forwardly elongated, substantially oblong shape (as shownin FIG. 11B) when viewed from top, which oblong shape has a width W2(FIG. 11A), as measured on the floor 82 when viewed from front, that issmaller than the width W1 shown in FIG. 10A, and also has a larger depthL2 (as shown in FIG. 11C) than the depth L1 shown in FIG. 10C whenviewed from laterally. The detection area represented by the narrow areaN is conveniently employed for a sensor suitably used in associationwith an automatic single door or swinging door 81A.

When the object detecting device D is used in association with anautomatic door system 50 shown in FIG. 12, by the operation of atransceiver circuit 25 provided in the antenna module 4, the antenna ATin the antenna module 4 radiates the sensing wave in the form of amicrowave, and the sensing wave reflected from an object such as amoving human body can be received by the transceiver circuit 25 throughthe antenna AT. When the frequency of the sensing wave reflected fromthe object and subsequently received by the transceiver circuit 25undergoes a change by the Doppler effect, such change can be detected bya detecting circuit 26. The detection result given by the detectingcircuit 26 is then supplied to an external door control circuit 27,shown in FIG. 12, through a wiring connected to a connection terminal 8shown in FIG. 2, to control selective opening or closure of theautomatic door.

As discussed above, in controlling the automatic door, orientation ofthe antenna AT in the antenna module 4 can be suitably selected inconsideration of the environment in which the object detecting device Dis installed. Specifically, in the case of the automatic double door 81shown in FIG. 10, the antenna module 4 has to be turned about the thirdaxis R3 to cause the antenna AT to be oriented as shown by the solidline in FIG. 7 so that the detection area can be set as the wide area asshown in FIG. 10. On the other hand, in the case of the automatic singledoor as shown in FIG. 11 or the automatic swinging door, the antenna AThas to be oriented as shown by the broken line in FIG. 7 so that thedetection area can be set as the narrow area as shown in FIG. 11.

With the object detecting device D having the three-axis adjustmentcapability according to the present invention as hereinbefore described,not only can the detection area be adjusted in the leftward andrightward direction (the first horizontal direction) substantiallyparallel to the door and also in the forward and rearward direction (thesecond horizontal direction substantially perpendicular to the firsthorizontal direction), but also depending on the environment in whichthe object detecting device D is installed, selection of one of the widearea W shown in FIG. 10 and the narrow area N shown in FIG. 11 can beeasily and quickly performed on the site of mounting the device D. Inparticular, since the setting of one of the wide area W and the narrowarea N can be easily accomplished by turning the antenna module 4, thereis no need to use two dedicated antennas, one for the wide area W andthe other for the narrow area N, and, therefore, the number of componentparts employed in the detecting device D can advantageously be reduced.Accordingly, the object detecting device D can be manufactured at areduced cost, having a compact size and an excellent handlingcapability.

It is to be noted that although in the foregoing embodiment the antennaAT has been shown and described as employed in the form of the wire, itmay be in the form of a patch antenna made of metallic foil. Also, theobject detecting device D of the present invention can be used not onlyas a sensor for the automatic door, but also as a security sensor fordetecting an unauthorized entry of an intruder and then issuing awarning output.

1. An object detecting device having a three-axis adjustment capabilityfor transmitting and receiving a sensing wave through an antenna, whichcomprises: a support platform; a first holder supported by the supportplatform for rotation about a first axis; a second holder supported bythe first holder for rotation about a second axis lying perpendicular tothe first axis; and an antenna module including the antenna andsupported by the second holder for rotation about a third axis lyingperpendicular to the second axis.
 2. The object detecting device havingthe three-axis adjustment capability as claimed in claim 1, wherein eachof the first and second holders is of a semispherical configuration. 3.The object detecting device having the three-axis adjustment capabilityas claimed in claim 1, wherein the support platform includes a basemember having a substrate and adapted to be secured to an externalsupport member, and an inner cover for covering the base member, thesubstrate having electronic component parts mounted thereon, and whereinthe first holder has a lower outer peripheral portion sandwiched betweenthe base member and the inner cover.
 4. The object detecting devicehaving the three-axis adjustment capability as claimed in claim 1,further comprising a first intermittent engagement for intermittentlyengaging the first holder with the support platform to provide a feelingof a click as the first holder rotates relative to the support platform.5. The object detecting device having the three-axis adjustmentcapability as claimed in claim 1, further a second intermittentengagement for intermittently engaging the second holder with the firstholder to provide a feeling of a click as the second holder rotatesrelative to the first holder.
 6. The object detecting device having thethree-axis adjustment capability as claimed in claim 1, wherein theantenna module is mounted on a top mount of the second holder bysandwiching the top mount between a holding member for holding theantenna and a back plate, the holding member and the back plate formingrespective parts of the antenna module.